Chapter IV: Front Matter (4)

2. The finding of the trees in colonies points to a genetic variation. At first I was unable to account for the grouping of the trees, for I had expected to find immune or resistant trees singly, here and there. But if we adopt the hypothesis of a heritable protoplasmic variation--something in their "blood," so to speak, the explanation is easy. We know that chestnut fruits or nuts do not travel far, like the seeds of willow, poplar, maple or ash, and therefore, in any given stand of chestnut, if we could go back from generation to generation into earlier time, most probably the majority of the trees would be found to have arisen from a common ancestor, although of course a few outsiders would have found their way into the group, carried by squirrels or other animals.

3. In a considerable number of cases all the members of the same group of coppice trunks from an old stump show a similar degree of resistance. To attribute such a condition as due merely to chance, occurring as often as it does, would be placing a pretty large burden on chance; and since the coppice trunks are all off-shoots of the same plant, the condition is what one would expect were the resistant quality in inherent character. A correspondence of degree of resistance was also noted, in the inoculations made on branches, trunk, and basal shoots of the same individual tree.

Experimental work is being carried on at Washington to test out the truth of this hypothesis, i. e. to see whether or not the disease resistance is really heritable. The work is being carried on in connection with the propagation of other resistant stock, Chinese, Japanese, etc.; and, as soon as the department is sure of the product, the results will be distributed to nut growers and others who are interested.

In the meantime we can all help by being on the lookout for resistant native trees. I believe they will be found in many places besides the New York region.

FOOTNOTES:

[1] Illustration for this paper will be found opposite page 64.

[2] Metcalf, Haven & Collins, J. Franklin. The Control of the Chestnut Bark Disease. Farmer's Bulletin--467, 1911, P. 5.

[3] Anderson, P. J. & Rankin, W. H., Endothia canker of chestnut. Cornell Univ. Agri. Expt. Sta. Bulletin 347, 1914.

EVENING SESSION

SANITARIUM GYMNASIUM, at 8:00 P.M.

President Reed in Chair

DR. J. H. KELLOGG: Ladies and Gentlemen: Battle Creek has the honor today and tomorrow to entertain the Northern Nut Growers' Association. This association with other associations having similar purposes, is undertaking to do, it seems to me, one of the most important things that can be done for the American people--to show us how we can get our nitrogen, our protein, and our fats without the livestock industry which is wasting at least nine-tenths of the grain, or in fact at least nineteen-twentieths of all our foodstuffs. The great cause of the high cost of living at the present time is that the pigs and the cattle are eating up our corn and other good things that we ought to eat ourselves. If we had a sufficient area of land, perhaps even the sides of our roadways and railways planted out to black walnuts and other good nut trees, we would have all the protein and fat we needed, perhaps as much as we are getting now, and more, and the cattle industry might be entirely dismissed from consideration, and a great deal of labor would be saved. I am sure that there is no place in the whole United States where this Association could have a heartier welcome than here in Battle Creek, or where people could be found who would appreciate its labors any more. You are going to have a very interesting program tonight. We are favored with visits from very distinguished gentlemen from all over the United States, among others Dr. Robert T. Morris, the nestor of American surgeons has come all the way from New York to tell us about some wonderful discoveries he has made, and a fatherless walnut tree he is cultivating, and other things that will be of great interest to us all I am sure. I take pleasure in introducing to you the president of this Association, Mr. W. C. Reed, of Vincennes, Indiana. Mr. Reed.

PRESIDENT REED: We are simply continuing our program. This afternoon we were in session at the Annex and moved over here this evening so as to be able to present what we have here so we could entertain more of you than we could over there to advantage. You know that most all men have a hobby along some line or other, and those who constitute our leaders, whom we have to look to, and along the line of nut trees of different species and so on, we have learned to look to Dr. Morris as one of the leaders. I have great pleasure in introducing to you Dr. Robert T. Morris, of New York, who will address you on the hickory.

NOTES ON THE HICKORIES

ROBERT T. MORRIS, M. D., NEW YORK CITY, N. Y.

When people speak of the "hickory" without qualification, they are apt to have in mind some one kind of hickory which belonged to their boyhood environment. All other kinds which they happened to know, were qualified in some way, very much as the word "fish" in Boston stands for the codfish only, other kinds of fish in the world being described by qualifying names. In the northeast the hickory means the shagbark. In Missouri it means the shellbark. Elsewhere the pignut and the mockernut are called "hickory." Interest in the subject has increased so rapidly of late years that we must all of us be more particular in our descriptions and add qualifying names, speaking always of the shagbark hickory, pecan hickory, or bitternut hickory as the case may be. Sargent describes fifteen species of hickory and in addition a large number of varieties by environment and by hybridization. There is a Mexican hickory, making sixteen species for the North American continent, and the late Mr. F. N. Meyer, Agricultural Explorer from Washington, has found a hickory in China. Previous to this discovery, it was believed that the hickories belonged to the North American continent only.

Botanists divide the hickories into two groups, Apocarya and Eucarya. For convenience in every day conversation, it might be well for us to speak of the "open-bud" group and the "closed bud" group. _Apocarya_ or the "open bud" group, includes the pecan hickory, _Carya pecan_, the bitternut hickory, _Carya cordiformis_, the bitter pecan, _Carya texana_, the water hickory, _Carya aquatica_, the nutmeg hickory, _Carya myristicaeformis_, and the Chinese hickory, _Carya cathayensis_. The winter buds of this group will be seen on examination to show the minute, snugly curled-up leaves which are ready to burst forth when the springtime sun opens the fronds of the ferns which have forced their way through the hard ground with clenched fists. The scale buds in the open-bud group do not cover the tiny leaf forms completely.

In _Eucarya_, or the "closed-bud" group, stout scales close the bud completely against the snow and ice of wintry days, so that we see scales only when looking at the bud. The closed-bud hickories include the shagbark, _Carya ovata_, the Carolina hickory, _Carya Carolinae-septentrionalis_, the shellbark, _Carya laciniosa_, the mockernut, _Carya alba_, the smooth-bark hickory, _Carya leiodermis_, the pallid hickory, _Carya pallida_, the close-bark pignut, _Carya glabra_, the loose-bark pignut, _Carya ovalis_, the Florida hickory, _Carya Floridana_, the Buckley hickory, _Carya Buckleyi_, and the Mexican hickory, _Carya Mexicana_.

Hickories which have nuts with a bitter pellicle, all belong to the open-bud group. These are the bitternut, Texas hickory, and water hickory. Hickories with scaly bark are found in both groups. In the open-bud group, the trunk of the water hickory carries long loose bark strips attached by one end, and in the closed-bud group, we find this characteristic belonging to the shagbark, shellbark, Carolina hickory, and to one of the pignuts, Carya ovalis. That takes us to another occasion for a note. What do we mean by "pignut?" In the North, this term is applied to Carya glabra and Carya ovalis. In the South, it is applied to Carya cordiformis. A name so well established, will have to be retained, but in our Association it will perhaps be best to have an understanding about which one of the hickories the common name pignut should belong. So long as it already covers two species in the North as opposed to one in the South, there are already two votes to one in favor of retaining the name pignut for Carya glabra and Carya ovalis. We may describe these in plain language as the smooth-bark pignut and the loose-bark pignut. The reason for choosing the name "loose" instead of "scaly" is because we are pretty well agreed upon applying the name "scalybark" to the Carolina hickory, the name "shagbark" to Carya ovata, and the name shellbark to Carya laciniosa. The name bitternut may safely be allowed to remain with Carya cordiformis because the other two nuts with bitter pellicle already have distinctive names, Carya aquatica being called water hickory and Carya texana being called bitter pecan. By making fixed points in nomenclature in this way we may head off the confusion which will become worse confounded as the interest in hickories becomes rapidly enlarged, if our committee on nomenclature does not take some decisive step.

Concerning Latin nomenclature, we have further troubles for settlement. Hicoria is the oldest generic name and naturally should have priority but the Vienna Congress of Botanists adopted Carya. So far so good (or bad). Now comes our trouble in giving specific and varietal names. The binomial is clearly applicable enough for species, Carya pecan, for example, but when we come to varieties of the pecan there are two kinds of varieties to be considered, those by environment and those by hybridization. In cases of natural variation we are still within accepted resources in nomenclature by saying for example, Carya pecan, var, Stuartii. When naming hybrid varieties, however, I would suggest that in advance of the abbreviation "var", we place the abbreviation "hyb." thus reading for Brown's pecan, "Carya pecan, hyb. var. Brownii," instead of "Carya Brownii," which latter binomial would throw it among the species. In view of the fact that we are to have in the future hundreds of named hybrids, it seems to me that we must adopt some such definite method for convenience promptly. This method of naming, relates to convenience and is applied to the most evident parent. As a matter of fact, in horticultural circles we are doing precisely that sort of thing, speaking, for example, of "Brown's pecan" meaning a nut which we recognize as being a hybrid, brought to attention by Brown but with the pecan as parent most strongly in evidence.

When I was a boy, the only hickory nuts of any sort available, were those collected from wild trees. The popular boy was one who knew of some trees which furnished the best nuts and who did not keep the news to himself. The squirrels knew the best nuts as well as the boys did and they would go past many hickory trees along fences and groves in order to congregate in the ones which had the nuts with the thinnest shells and plumpest meats of best quality. In the early morning hours I have seen several squirrels in one particularly good hickory nut tree and not a single squirrel in a tree completely filled with nuts, though its branches touches those of the first one. Men are quite as intelligent as squirrels in some respects. Here and there attempts were made at propagating fine hickory trees of various species by planting nuts. It was not generally known at that time that the hickories were so thoroughly crossed like the apples, that they would not reproduce true to type from seed. Attempts were then made at grafting which were mostly failures for many years. We are now on the verge of a great development in hybridization or crossing of choice kinds of hickories and in determining upon which stocks the different kinds of selected hickories may be grown to best advantage. Hybrids between varieties of hickories occur frequently in nature and hybrids between species of hickories occur occasionally. A number of these accidental hybrids have been discovered and some of them are now being propagated. For the most part they do not represent the best quality of the best parent but it is a notable fact that the bitterness of kinds with the bitter pellicle appears to be a recessive character and disappears usually from hybrids between species in which one parent has a bitter nut. Unfortunately, the finer extractive which give character to the nut of the better parent are prone to disappear also. This is in line with our experience in mixing of characters along Mendelian lines. Given a sufficient number of hybrids and we shall have here and there one with spectacular characteristics of special value.

Now that horticulturists at the present moment are turning so freely toward the idea of producing quantities of hybrids artificially, the next generation will see hickory nuts which were not dreamed of in the days when I was a boy. The crossing of hickories is not difficult work. We simply remove the male flowers from branches carrying female flowers before the male flowers have begun to shed their pollen. The female flowers are then covered with oiled paper bags tied over them for protection and when the danger from self pollination has passed, we take off the bags and add a little pollen which we have kept for the purpose--pollen from some trees bearing remarkably valuable nuts.

Nuts resulting from this cross pollination when planted, give us new varieties of trees which never have been seen before by anybody and that is so interesting that very many people will probably take up hybridization as an incident in recreation. Some of the hybrids will bear very early in their history and others very late. If one is impatient to determine at once which ones are to be valuable, he can hurry the process by grafting a number of cuttings from young seedling trees into the tops of larger trees which are already bearing--labeling each graft, so that he may keep track of the seedling stock from which it came. It is possible to put one hundred or more seedlings in the top of some stock tree at one time.

One reason for delay in propagation by grafting is because the hickories like many other trees are slow in making repair of wounds. Grafts usually perished before being accepted by the stock under grafting methods that were in common use. The best step forward in grafting method for hickories is one that I obtained from Mr. J. F. Jones, Lancaster, Pennsylvania. He tells me that he obtained the method from its originator, Mr. E. A. Riehl, Godfrey, Illinois. This consisted in covering the entire graft, buds and all, with melted grafting wax and including also all of the wound and wrapping of the stock. The buds make their way through this grafting wax without any difficulty, but the grafting wax used by Mr. Jones contained lamp black and that used by Mr. Riehl consisted of a beeswax and rosin mixture. It was found that these seemed to be applicable in the North but not farther south in the hotter sun. Examining into the reasons for this, it seemed to me that in all probability the black grafting wax used by Mr. Jones and the brown or amber grafting wax used by Mr. Riehl, would naturally allow the heat rays of the sun to pass through to the graft while halting the actinic ray of light. The latter is extremely valuable for promoting the activity of chlorophyl, which acts only in the presence of light and in the best way in the best light. The heat rays might have certain destructive qualities. With this theoretical idea of the situation in mind, I employed melted paraffin in place of the grafting wax, covering the scions completely as well as the wound in the stock and the wrappings. This immediately proved to be a success. In fact, it appears to have changed the entire subject of grafting nut trees in such a way that any intelligent boy employing this method can now do better hickory nut grafting than would have been possible at the hands of an expert two years ago. The melted paraffin fills the interstices in which sap might collect and ferment, but at the same time, hardening so quickly that it does not introduce the danger of extension between points of contact with scion and stock. The second point of value consists in allowing the actinic ray in the sunlight to act upon the chlorophyl in bud and bark of the scion and it does not attract the destructive heat ray. This is perhaps the most important single point of value and due to the transparency of the paraffin. Third, the paraffin coating, impervious to air, maintains the sap tension equally in the course of fluctuation between negative and positive pressures occurring between night and day, and under varying conditions of light and temperature. This maintenance of equalised sap tension, I believe to be important. The paraffin is waterproof and prevents evaporation from the scion, which otherwise is prone to dry out before granulation of the wound has taken place in the hickories, as in other species which callus slowly. Fifth, under the paraffin coating of stock and scion, the plant apparently does not have that anxiety which would otherwise lead it to introduce the protective feature of superization, the spreading of a corky layer over the wound surface between stock and scion, thus introducing a mechanical obstacle to union.

This method of grafting has extended the grafting season for nearly two months, apparently. Formerly, I hurried to get all of the grafts in while buds were bursting, in early May. During the season of 1919 I grafted hickories up to August sixth experimentally. The last grafts which caught well in a practical way were put in on July twenty-first. After that the proportion of catches was small and the growth feeble. Incidentally, it may be remarked that filberts grafted as late as August sixth, did perfectly well. The scions employed were cut in late winter and kept in the sawdust of my icehouse. I formerly supposed that ice beneath the sawdust was important, but this year I could not get ice and the scions kept just as well. In July, experiments were tried with grafting directly from one tree to another, using wood of the season's growth. This worked well with hazels, but not with hickories or walnuts, only one out of many hickory grafts catching. That one, however, is significant and I hope to work out principles which will allow of direct grafting of hickories as readily as may be done with the hazels.

When a hickory graft is to be inserted into a small stock or branch, the ordinary cleft graft does well. In stock recipients much larger than the graft a side cleft of the width of the scion only is desirable, or better yet the "split bark" method devised by Mr. E. A. Riehl. A straight split is made in the bark of the end of the stock, and the graft crowded down into this split so that it remains between bark and wood finally. My own method for large stocks, is what I have called "the slot bark method." This consists in turning down a width of stock bark measuring the same as the scion in width. When the scion has been inserted into this slot so made, the bark is turned up over it again and fastened there. By this method I have put scions in the trunks of trees nearly a foot in diameter and at any chosen point, sometimes several feet below the ends of cut branches. One may cut off the top of a large hickory tree and then peg the trunk full of scions by means of bark slots.

Another important point in hickory propagation work consists in the employment of the Spanish windlass for fastening graft and stock together. The old time wrapping of twine or of raffia had to be released in order to allow growth at the point of union of scion and stock. When cord is used it cuts deeply into the new growth, and raffia, which is placed on flat, will be burst open. In either case new wrapping is required at a precarious time, according to old methods. The Spanish windlass, which is used in surgery for controlling haemorrage, seemed to me to be applicable for fastening scions in place. It consists in a paraffined cord with ends tied in a firm knot but hanging loosely about the graft and wound. A wooden skewer or any small lever, is then inserted into the loose loop of cord and twisted about until the part of the cord about the graft wound is so snug that it holds the scion in place more firmly than it can be held by any other sort of wrapping. In order to prevent the cord from cutting into the bark, two shields of wood or metal an inch in length, are interposed between cord and bark. The lever of the Spanish windlass is fastened with a cord or with a galvanized nail in order to prevent the windlass from unwinding and the whole covered with melted paraffin. This may remain in place for two seasons without change, holding the scion firmly in place all of that time and requiring no attention. The growing stock separates the two shields very much as it might separate two stones in the field and automatically unwinds the Spanish windlass by sheer force, just enough to allow growth without any unloosening of its holding apparatus.

In hickory grafting, much experimental work remains to be done in the choice of stocks for grafts of different species. Almost all of the hickories that have been grafted upon the pecan hickory stock, seem to do pretty well upon that stock, but the converse is not true. The pecan apparently does not do well as a rule when grafted upon other hickory stocks, even upon those of its cousins in the open-bud group. The shagbark hickory, in my experience, has done best upon stocks of the shagbark or mockernut or pignut. A number of years, however, are required in some cases for determining that point. Shagbarks which I have grafted upon bitternuts have sometimes made a remarkably good start. Then at the end of three or four years they begin to slow up, while shagbarks on shagbark stock, starting slowly at first, surpassed the ones on bitternut stock finally.

In the spring of 1919, I topworked two trees standing near together and of about the same size (thirty feet) with Beaver hybrid (a cross between the bitternut and the shagbark). One of the trees was a bitternut and the other a pignut. Almost everyone of the grafts of the Beaver grew thriftily on the bitternut. Those on the pignut stock practically all caught and made short growth and then began to wilt back. Finally, only one shoot remained alive. This very striking object lesson will have bearing in varying degrees in all of our hickory grafting. According to my experience to date, hybrid hickories are grafted more readily than are straight species or varieties. They seem to have lost family pride and seem to take up with any friend offering economic support. In the case just quoted, however, caprice was shown by the Beaver hybrid which took eagerly to a host of the species of one of its parents. It refused to thrive on the pignut which did not represent either one of its parents although that same pignut stock would have been accepted by shagbark scions--the shagbark representing the other parent of the Beaver. This sort of experience throws open the entire subject in such a large way as to show what possibilities of success and failure lie before us in experimental work. The same method of grafting, the paraffin windlass method, was employed for these two trees which were neighbors.

Interesting experimental work is to be done in finding the extent to which different species and varieties of hickories may be grown out of their indigenous range. At Stamford, the bitter pecan from Texas, appears to be perfectly hardy but it makes very slow growth--sometimes less than an inch in a year. The Buckley hickory also from Texas, grows thriftly at Stamford and so does the Carolina hickory Pecans from the northern belt thrive at Merribrooke, but those from the southern belt have such a long growing season, that their new wood is not yet sufficiently well lignified to stand the winter well. Some of them pull through a mild winter in fairly good order, but on the whole they do not thrive.

The commercial side of hickory raising, is being worked out for the pecan only at the present time. We may assume that several of the other species of hickory adapted to growing in the north, will equal pecans in importance, eventually. The reason for that is because some of the other hickories stand quite as high as the pecan in food value and general excellence. At the time of writing, low grade seedling shellbark nuts from the West are selling in the retail market in New York for forty cents a pound. I have seen better nuts of this species being loaded on the cars in Ohio at fifty cents a bushel. The present New York price, to be sure, represents a profiteering war price. Fine grades of shagbark hickories and some of the hybrids will command prices equally high with prices for best pecans in the market of to-morrow.

VOICE: Will it be practical to plant nuts, get young plants, and then bud or graft them?

DR. MORRIS: Yes, that is what we do. It is practical to plant nuts for the purpose of getting a stock, but not for the purpose of getting nuts. But we plant them in the nursery rows, and then when they are two years old, preferably (some like three-year-old trees), we graft them over to good kinds in the nursery row; then they remain there for a year or two, and are transferred or sold. We now have members of this association who are experts in grafting nut trees who make that a business. It is not generally known that we have in this country three journals devoted wholly to the subject of nut culture. We have nurserymen who make a specialty of grafted nut trees of the very best sorts, so that one may perhaps take up this mode of farming more profitably today than almost any other sort of farming. One gentleman in Pennsylvania told me he made thirty thousand dollars on one crop of chestnuts two years ago, cultivated chestnuts. He had thirty acres, and no tree was yet fourteen years of age. His net profit beyond all expenses was thirty thousand dollars that year. There are probably very few professional men who make more than that a year. Many men are making good, comfortable incomes out of their nut orchards. It is the best insurance against the needs of old age, the best sort of life insurance.

VOICE: Do you use anything besides the hickory as stock for grafting on?

DR. MORRIS: Yes, we have some experimenting to do in order to learn which stock will best serve for a certain variety. We find that one species or variety of hickory will accept other varieties of that species well, but perhaps it will not accept another species. We do know that certain kinds do remarkably well on certain stocks; but the entire range of that subject has not as yet been worked out.

QUESTION: Does the stock you graft on have any effect on the quality of the fruit?

DR. MORRIS: The stock on which you graft is supposed to have no effect at all on the quality of the fruit. But there are some exceptions. We learned that in orange grafting. A naval orange grafted on the wild orange stock might be raggy, not full of juice; while when grafted on the trifoliate orange stock might be heavy and full of juice. So in that case the stock did have some influence upon the graft; and there are other instances. But as a rule we assume that the stock has no influence upon the graft in regard to the validity of character.

QUESTION: Are pecans a variety of hickory?

DR. MORRIS: Yes, pecans are hickories. The Indians gave it the name of pekan. The French spelled it pecanne, so that has been spelled as the pecan, without the necessary other part of its name, hickory. We should always say pecan hickory--always.

DR. KELLOGG: Dr. Morris, how old hickories may be used for grafting?

DR. MORRIS: I have experimented with trees up to fifty years of age; but the most satisfactory work, perhaps, is done with trees that are not more than fifteen or twenty years of age and three or four or five inches in diameter. Those are the best trees to work with. If we cut off the limbs of a very old tree and try to top work it, it means an enormous amount of work on the part of the orchardist, more work than my employees like to give it. But one may topwork a tree of almost any age, preferably a tree less than twenty-five years of age; and by choice I should say trees not more than ten years of age. We have experts in the audience better qualified to speak on that subject than I am.

QUESTION: Do you prefer the melted paraffin to the old-fashioned way of using bees wax?

DR. MORRIS: The old-fashioned beeswax had a certain color, and the black wax with charcoal, with lampblack, both turned the light ray and allowed the heat ray to enter so that the amber of the old resin wax, and the black of the black wax both allowed damage to occur to the tree, in the South particularly, in a hot climate early in the summer, prevented our grafting in the summer because of the turning away of the light ray that was wanted and the absorption of the heat ray that was not wanted. The melted paraffin being perfectly transparent, allows the light ray to set the chlorophyl into activity. All the life processes of the tree are carried on under the influence of the green chlorophyl grains, and these work only in the presence of light.

QUESTION: Can you successfully graft a pecan on the pignut?

QUESTION: What is the best stock to graft pecan on?

DR.MORRIS: Pecan stock, I think. I do not think we have anything better. Mr. Reed and Mr. Jones are both experts in that field. They have grafted hundreds of thousands of trees.

PRESIDENT REED: I think the pecan is the best. The hickory will grow on the pecan very well, the shagbark hickory, but it will not do to change it with any degree of success.

DR. MORRIS: The shagbarks will grow fairly well on pecans, but the pecan not well on the shagbark. It is best I think to put shagbarks on shagbark or shellbark. But they do well on pignut. I have got some very good shagbarks on mockernut. On bitternut they grow fast, but at the end of eight or ten years are inclined to slow up. Shagbark can be put on, I suppose, ten other kinds of hickory, but the pecan can not.

QUESTION: How many grafts would be necessary on a nut tree twelve inches in diameter?

DR. MORRIS: I should say you would probably have to put in fifty. I would cut off the branches down to about two inches or an inch and a half in diameter, and that might leave fifty stubs to graft. Graft all of them, is one way to do it. Having done one that way, you will then become familiar with the entire subject.

QUESTION: What is the best time of year?

DR. MORRIS: I don't know. Some time ago the American Agriculturist said to its readers that there is disagreement about the best time for pruning peach trees. Let us hear from all our readers. So all of the readers wrote expressing their opinions, and the editor said, "Summing up all of the opinions, the entire testimony in the case, we have decided that the time to prune your peach tree is when your knife is sharp." I had always supposed that the best time for grafting was when the buds were first bursting in the spring, always held rigidly to that, and at that time of the year was in a great hurry. I dropped professional work and lost hundreds and even thousands of dollars in order to see this work go ahead; it is more interesting than professional work. And now this year, with this new method, I have grafted right straight on up to the first of August, and everything growing--deliberately, all through the summer. So that now, at the present moment I do not know. A year ago I could have told you. When I first graduated in medicine, I could answer any question in medicine. After forty years of surgery, I am puzzled over a great many questions. It is the same way regarding grafting.

QUESTION: In summer grafting do you remove the leaves from scions?

DR. MORRIS: In summer grafting I have used for the most part scions I have kept in the icebox in sawdust. I have formerly put in twenty or thirty tons in my icehouse for my family to use during the summer. Last winter we could not get any ice, and my scions were just as good kept in the sawdust as if we had had ice; and I grafted those scions in August and the grafts are living. I have also cut off the leaves in grafting, but that is new and you can not depend on it,--stop at one tree, cut off a piece of it, and put it on another tree and have it grow. I have never done that until this year, and it does not succeed in a very large percentage. It is not practical. It can be done--I have proven that; but it is not practical. The best way is to use your scions from last year that have been kept in cold storage in sawdust or leaves.

DR. KELLOGG: When should the scions be cut?

DR. MORRIS: There is some disagreement about that. Almost all scions may suffer a little winter injury. Some men prefer to cut in the early part of December before we have had any hard winter, then keep them in cold storage during the entire year, moderately moist, or protected in sand, leaves, or stratification. But I have always preferred February myself, cutting them the last of February before the buds begin to start, then put them in sawdust in the icehouse or cold storage, or bury them under a thick layer of leaves. For budding you transfer immediately. In fact, budding technically comes under the same physiologic principles as grafting. In budding I do that work in my place at Stamford, Conn., about the latter part of July or early August.

DR. KELLOGG: Do you use the same method in transferring buds?

DR. MORRIS: Yes, I fix them the same way as I do the graft and cover everything with paraffin. I have even had a little short side graft grow using this paraffin method, a graft two or three inches long.

DR. KELLOGG: Tell us about those fatherless walnuts.

DR. MORRIS: In the course of crossing the nut trees, we supposed, as a matter of course, that we must always have the pollen from one tree, or from a tree which bore the staminate or fertilizing flowers, in order to develop nuts or fruit of any sort; but on one occasion I covered a lot of Chinkapin female flowers with paper bags; I didn't have pollen enough to go around and left the bags on because I happened to be too lazy or too busy to pull them off. About a month later when I did take them off I found a full set of chinkapin nuts under those bags. They had received no pollen. That was an observation of a good deal of interest. It may have been that they had gone on by what we call parthenogenesis, and we had the children without the father, had the female parent only, the fatherless chinkapin. It sounds sad. I followed up the experiment with other nut trees, and found that not infrequently we may develop fatherless nuts. The effect will be, according to natural law, to intensify the characteristics of one parent. The female which bears this fruit, this child, without a father, will give to that child an intensification of her own characteristics. That will be the effect of parthenogenesis. That may be continued through several generations perhaps; we do not know. It is new, quite new. (Applause).

PRESIDENT REED: The next topic is the Digestibility of Nuts, by Mr. Cajorie, of Yale University.

THE NUTRITIVE VALUE OF NUTS

F. A. CAJORIE, YALE UNIVERSITY, NEW HAVEN, CONN.

Mr. President and members of the Northern Nut Growers' Association: It was with great pleasure that I accepted the invitation of your Association to be present at this convention and give a discussion of nuts and nut production, from the point of view of their nutritive or food value. During the last few years our knowledge of nutrition and the parts that individual foods may play in the diet has been greatly increased and in the light of the new discoveries, it is interesting and valuable to view the place that nuts hold.

As you are well aware, nuts have been used as foods by the peoples of the world. In many places nut products have made up a very appreciable part of the diet. Chestnut flour is extensively used in Southern Europe. Among the peasants of Tuscany, chestnut flour forms a considerable part of the total diet. In this region, also ground acorns are made into bread with cereal flours and in this form is a common food. The hazel or filbert nut is also seen in the form of flour on the shores of the Black Sea. Races living in the tropics have utilized the many varieties of nuts indigenous to tropical climes such as the coconut, Brazil nuts, Java almond, Paradise nut, candle nut and African cream nut. In the Orient, the lichi, ginko and water chestnut, and in Italy and India the varieties of the pine nut are used to considerable extent.

In America, with the exception of a few localities and among a limited class of people, nuts have never made up a staple part of our dietaries, rather they have been used as tasty supplements to otherwise complete menus. That they are prized as adjuncts and are sought after is strikingly shown when we see in our markets not only the products of our native American nut trees, the hickory, walnut, butternut, chestnut, pecan, beechnut and pinion, but the Brazil nut, filbert, English walnut, peanut, coconut, all of which are derived from foreign countries or from trees originally imported to America from other lands.

Analysis of nuts have shown them to be of two types, one rich in fats and protein, the nitrogen containing component of our foods and the other relatively rich in carbohydrates, or starches. With the exception of the chestnut, and the coconut, most of our more common nuts belong to this first class, and chemists have pointed out that in these nuts we have a concentration of protein and fat seen in no other class of foodstuffs. For example, the protein-fat rich nuts have a percentage of protein varying between 15 and 30% and a fat content of 50-70%; compare this with other foods that we think of as being concentrated; eggs, 12% protein and 10% fat; cheese 28% protein, 37% fat; round steak, 20% protein, 14% fat; and bread, 10% protein. This nutritive concentration in nuts places them in a unique position among our natural food products. Our cereals, meats, fruit and vegetables all contain more or less water or refuse that reduces their concentration, while in nuts we find a compact form of almost pure food.

We are dependent on foods for the source of energy that is necessary to perform our work and maintain our body temperature much in the same way that a steam engine is dependent on the fuel supplied it to perform the mechanical tasks assigned to it, and this fuel value of foods in turn, depends on the amount of protein, carbohydrate and fat, particularly the latter, that are present in the foods. At once we see, in our concentrated nuts, a tremendous source of energy, provided that we can digest these nuts and make this energy available.

Despite the fact, as revealed by chemical analysis, that in nuts we have a source of protein and fat in a concentration rarely seen in foods, there have been relatively few experiments to actually determine the digestibility. Prof Jaffa at the California Experiment Station was the first to make a comprehensive investigation along these lines. He made extensive digestion tests on men using most of the more common American nuts. His results, as reported in a bulletin of the U. S. Department of Agriculture, indicated that nuts when they made up a substantial portion of the diet, were well digested by those who ate them and gave no intestinal disturbance or discomfort.

Nuts have had a reputation for indigestibility that was wide spread, not only among people in general, but also among physicians and dieticians, and even Prof Jaffa's clear cut experiments failed to dispell this idea of indigestibility that had been empirically assigned to nuts. A few years ago, a rather extensive series of digestion experiments were inaugurated at Yale University in an effort to settle this question of the indigestibility of nuts and also to test out some of the commercial nut products to find what effect roasting, boiling, and other processes that nuts are subjected to, had to do with the digestibility. Through the courtesy of Dr Kellogg of Battle Creek, it was possible to follow up these experiments with a series here at Battle Creek. It is the result of these tests that I wish to speak of today. One word regarding the method which is the conventional one for such experiments. The amount of food eaten by the individual or animal is weighed at each meal and the composition determined by chemical analysis. The intestinal output is collected, weighed and analysed. From the difference in any substance such as protein in the food and the protein which appears in the body refuse, the amount digested and absorbed or utilized by the body is easily determined. For example; if 10gms. of nitrogen were eaten in the food and one gm appears in the feces, we say that the coefficient of digestibility of that nitrogen is 90%, that is 9 of the 10 gms. eaten were absorbed by the body. The average of a great many such tests on mixed diets has the following standard coefficient: protein 93%, fat 95%, and carbohydrates 98%.

Our digestion experiments show the following results: for protein digestion of nuts, almond 89%, peanut 84%, pine nut 89%, Eng. walnut, 83%, Brazil 88%, and coconut 88%. In all cases the carbohydrate coefficients are 98 or 99%, and in the case of the carbohydrate rich chestnut, normal digestion took place after the nut was heated so as to rupture the starch granules. In all of these cases the nut made up a substantial part of each meal and was eaten in large amounts. The experimental subject, experienced no digestive troubles or discomforture whatsoever except in the case of the English walnut, which evidently contains some irritating substance that causes diarrhea. Except for the pecan which gave rather low utilization, the protein of nuts was digested to a high degree that compares most favorably with our ordinary foodstuffs.

How then explain the undoubted discomforture that many people experience after eating nuts? I believe that the explanation rests on the fact that our common American way of eating nuts, is not the rational way. We would not consider topping off a heavy meal with eggs, meats or cereals or to eat these in large quantities between meals realizing that we are exposing ourselves to possible digestive discomfort. No more then, can we expect to so eat nuts which are even more concentrated or "heavy" than meat or eggs without occasional discomfort. Unpleasant results from so eating does not condemn the nuts as indigestible, rather it condemns our mode of using that nut. Further, we must recognize that the nut is a hard, compact substance and that unless completely masticated, is not readily penetrated by the digestive juices of the alimentary canal. This was very well brought out in our experiment with dogs. The dog bolts his food and where there were large fragments of the nut in the food, they appeared almost unchanged in the feces, while if the nut is ground fine before feeding, it was readily digested. Comparisons of nut butters and nut pastes with the whole nut also brought out this point. The completely commuted nut butters showed consistently higher degrees of digestion than the whole nut.

With the exception of the starch rich chestnut, the heating of the nut did not seem to effect the digestibility whether this heat was boiling, steaming or roasting. The raw nut apparently is as well digested as the heated products. No differences were found between nut butters whether the process involved steaming or roasting of the nut. I am not speaking of the enhancing of the flavor that heating may bring about, but only of the digestibility.

Dr. Longworthy and his co-workers in the Dept. of Agriculture have investigated in recent years the digestibility of many vegetable oils, among them nut oils, and have found as high a percent of utilization with these as with butter and our other common animal food fats.

I believe that we are fully justified in the conclusion that nuts and nut products, if rationally used in our diets, are as digestible and fully as valuable from a nutritional point of view as our other foodstuffs.

While we can now definitely speak of the high digestibility of nuts, it is necessary to consider other phases of the part played by foods in nutrition. The fact that a food after being taken into the body can be broken up by the digestive juices of the alimentary tract, and the products absorbed, as we have found, to be the case with the nuts, is not the end of the story of the function of that food.

About fifteen years ago, it was discovered that during the progress of digestion, the protein materials are reduced by the digestive juices of our stomachs and intestines to smaller chemical compounds, and that it is these smaller fragments of the protein molecule that are absorbed into the blood and are used to build up our muscles and tissues. These fragments or "building stones" as they have been fancifully called, are all of a distant class of chemical compounds known to chemists as amino acids. Eighteen of these acids have been found as the products of protein digestion.

We may conceive of our bodies as being continually supplied with a mass of these 18 building stones from which it selects the kind and number that it needs to repair the everyday wear and tear of the tissues and in the case of the growing child builds new structures.

Since the date of this important discovery regarding the fate of indigested protein, it has been found that with few exceptions, the body is not able to manufacture these amino acids or to change one kind into another, and must depend on the protein eaten, for a supply of the various kinds that go to make up the body protein. Further it has been found, that many of our commonly used food proteins do not contain all 18 of these amino acids components. In some foods one, two, and sometimes more are lacking, or if present are in very small amounts. If our diet contained only proteins of an inferior grade, we can picture our body requiring building stones of various kinds to maintain the structure of the body and unable to obtain them due to the poor quality of the food, protein. Nutritional failure would be the result. The proteins then must be of the right quality as well as present in the proper quantities, to prevent mal-nutrition. Bearing in mind these facts, it is necessary in studying a food such as our nuts, to determine the kind of protein the individual nut contains as well as to know whether or not it can be digested by the body.

During the past few years, it has been found that we must have in our foods a certain amount of substances whose chemical nature is at present unknown and to which the name of vitamines has been given. It is not my purpose to discuss with you the many phases of vitamines and their relation to nutrition, but I only wish to impress upon you the fact that it is of the utmost importance for a dietary to contain these substances; fully as important as that the protein, fat, carbohydrate, and inorganic salt content shall be satisfactory. Lack of these vitamines brings on various evidences of mal-nutrition. One vitamine which is found in animal fats and the leaves of plants and is soluble in, and associated with fats, is, for that reason, called fat soluble vitamine. Another called the water soluble vitamine is widely distributed in cereal seeds, vegetables, and legumes. The third, the so-called antiscorbutic vitamine because of its action as preventative and cure for scurvy, is found in certain fruits and vegetables.

We then ask the next question: Are nuts adequate as far as their proteins contain these essential amino acids, and do nuts contain vitamines? That is, is their biological value as satisfactory as their digestibility?

Dr. Hoobler of Detroit, in a study of the diets of lactating mothers and wet nurses, a year or so ago, compared the value of proteins from animal and vegetable sources for the elaboration of milk. He found that a mixture of the almond, English walnut, peanut and pecan, furnished proteins that were equal to the animal food tried, and far superior to other vegetable proteins. Here then is evidence that nuts provide the necessary building stones to form milk that food par excellence for the newly born individual. Drs. Mendel and Osborn, experimenting on white rats have shown that the principle proteins of the Brazil nut will maintain animals through the growing period. Bureau of Chemistry workers and others have found similar results with the coconut and the peanut. I have now, experiments underway at New Haven, on the biological value of the filbert, English walnut, pine nut, almond, and pecan. While these tests are yet incompleted, it can at least be said that to date there is no evidence that the proteins of these nuts are in any way less satisfactory than those of the peanut or Brazil nut that have been thoroughly tested out.

As to the vitamine content, abundant quantities of water soluble vitamine have been found in the peanut and the coconut. Experiments that we have in progress as well as a series conducted here at Battle Creek under Dr. Kellogg's direction give promise to increase this list of vitamine containing nuts to include at least many of our common nuts. Along with our vegetable oils in general, coconut oil and peanut oil contain insufficient quantities of the fat soluble vitamine to maintain growth in young animals. Whether the other nut oils will prove more efficacious in this respect, is now under investigation. As far as I am aware, the antiscorbutic properties of nuts have not been studied.